Unpiggable Pipeline Solutions

Conference Program Abstracts



[1] Wax removal from large-diameter pipes using ice slurries

Steve Wheeler, iNPIPE Products, Brompton on Swale, UK
Dr. D. Rhys, Suez Advanced Solutions Limited, Bristol, UK

Ice Pigging is a cleaning technique, mature in the water / wastewater industries, which is being developed for the Oil and Gas industry.

A high-solids ice slurry is pumped under pressure to deliver a wall shear stress on the pipe, cleaning it through physical abrasion. Made of just water and salt, ice pigs do their cleaning, unblocking, debris entraining and transport before melting back into their original components (commonly salt and water); offering a physical clean thousands of times more effective than flushing, without chemicals or risk of getting stuck.

The trails, which are the subject of this paper were commissioned by Royal Dutch Shell plc, using funding from their Gamechanger innovation program.

[2] Small-diameter cleaning pigs

Doug Batzel, Batzel Engineering, Moosic, PA, USA

The paper reports on the solution to a problem cleaning small diameter pipes, 1” through 4”. There was a need to clean coil tubing after it was used in a well bore where the product pumped through tubing stuck to the walls. Flushing was not sufficient to dislodge the debris. Premature failure of the tubing due to corrosion was a major problem.

In the coil tubing business, the only solution was to use a piece of high density foam and flush it through the tubing. Flushing was ineffective. Adding to the problem is the constantly changing curvature. Another problem was that effective miniature brushes were nonexistent.

Once a pigging solution was engineered, the next problem was that, since the coil tubing was mounted, the pig needed to turn a 90-degree bend without getting stuck, harming the pig, thereby reducing the ability to conform to the constant radius change, damaging the bristles thereby limiting the cleaning effectiveness and the pig could not damage the inner surface of the coil tubing which would allow corrosion the get a foothold. And the pig should be reusable.

This paper will discuss all of the steps taken to design and build a successful pig.

[3] Not all pipelines are constructed equal – how to determine the right inspection technology based on expected damage mechanisms

Dan Revelle and Ron Maurier, Quest Integrity, Houston, TX, USA

Determining an appropriate inspection technology is the critical first step in performing a successful pipeline inspection. A number of significant and potentially prohibitive factors must be considered to determine an inspection method that accurately detects damage mechanisms likely present within a pipeline. Theoretically, typical damage methods including corrosion, erosion, pitting, third-party damage and deformation are reliably detectable by all pipeline inspection methodologies. However, circumstantial difficulties during pipeline inspections, including atypical environments, construction-related damage, and unusually hard-to-find defects require specialized detection. Having an understanding of what damage mechanisms are expected within any given pipeline largely affects the type of tool technology utilized during an inspection.

Damage mechanisms are not, however, the sole determining factor when choosing an appropriate inspection methodology. The operator must also take into consideration the pipeline’s accessibility, configuration, environmental constraints, product throughput and associated cost, as these factors can significantly limit a tool’s detection capability.

This paper will discuss the spectrum of damage mechanisms that cause integrity concerns for unpiggable pipelines, as well as the other critical factors that complicate the tool selection process. A specific focus will be on addressing each inspection methodology’s ability to successfully detect types of expected pipeline damage at specific pipeline locations. Although there are benefits in using various types of technologies to validate integrity (MFL, hydrostatic testing, ultrasonics, spot UT, etc.), there are a number of limiting factors to consider for each methodology, such as data coverage at bends, pipeline supports, pipe tees, operational constraints, and the full cost of each procedure as part of an integrity program. Real-world case study examples will be used to illustrate.

[4] Inline inspection of multi-diameter gas pipelines at low pressure

Stefan Krieger and Michael Pieske, ROSEN Group, Lingen, Germany
Stefan Vages, ROSEN Group, Calgary, Canada

Most of today’s gas transmission and distribution systems can be inspected using available inline inspection technology. While this is applicable to the majority of pipeline systems, a certain portion of pipeline segments remains unpiggable or difficult to inspect. When looking to properly assess the integrity of these assets, different options for data gathering are usually evaluated, e.g. hydro-testing, ECDA, and inline inspection. Since inline inspection is the preferred assessment method and often also the most cost effective, new solutions for these more complex pipeline segments are required.

Pipeline segments that cannot be inspected with available technology typically consist of multiple challenges at once. While each of these challenges individually has already been overcome — e.g. the passage of 1.5D 90° back-to-back bends, successful completion of surveys in a low-pressure environment, or the application of inline inspection in multi-diameter pipeline systems — the combination of several of them requires new systems to adequately address the corresponding problems.

The challenges related to successfully completing inline inspections of multi-diameter gas pipelines at lower pressure levels include:

  • Proper preparation of the pipeline for ILI — special multi-diameter cleaning solutions
  • Achieving the desired data quality
  • Reaching a balance between sufficient seal and reduced friction
  • Passage of complex pipeline features – e.g. back-to-back 1.5D 90° bends

The ROSEN Group is currently developing a suite of multi-diameter ILI tools — in particular 10/12", 12/16" and 24/30" tools among other sizes — that are specifically designed to accommodate the challenges of low operating pressures and complex pipeline geometries. The development program also encompasses the creation of cleaning solutions that effectively address the challenges posed by multi-diameter pipelines. These new inspection solutions provide pipeline operators with more options for gathering the same quality information on their challenging pipeline segments as on their already inspected segments.

This paper discusses the considerations going into the project, design requirements, testing programs, and relevant field experience. Additionally, the limitations of the technology in the corresponding environment will be discussed.


[5] Comparison and overlaps of tools for internal inspection of pipelines and in human blood vessels

Dr. Stephen Igo, DeBakey Heart & Vascular Center, Houston Methodist Hospital, Houston, TX, USA

[6] Nondestructive evaluation of heat exchanger tubes and pipelines using electromagnetic waves

John DeWees, WaveTrue, New York, NY, USA
Dr. Ronald Focia, Pulsed Power Laboratories, Edgewood, NM, USA

WaveTrue Science + Technologies, a pioneer in the field of using electromagnetic waves to detect external pipeline anomalies in cased and insulated pipe configurations and the monitoring of casing wax fill, has developed and is further refining and commercializing a new method for internal direct assessment that utilizes electromagnetic waves (EMWs) to non-destructively ascertain the condition of tube and pipe internals.  This patented method (US7940061), called EMW-I™, can be used to detect anomalies such as sludge buildup, water in natural gas pipelines, cracks, through holes, and corrosion on the internal surface of any metallic pipe or tube ranging from small diameter heat exchanger tubing to large diameter pipelines carrying natural gas.

EMW-I™ is similar to RADAR in the way that it works.  EMW-I™ relies on launching EMWs down the hollow space of a metallic tube or pipe and monitoring for reflections that occur from anomalies that may be present either within the hollow space, e.g. sludge, water or hydrocarbon buildup, or that disrupt the conducting surface of the pipe, e.g. cracks, corrosion or through holes.  EMW-I™ treats the tube or pipe under test as a cylindrical waveguide.  A cylindrical waveguide supports well defined transverse electric (TE) or transverse magnetic (TM) propagating modes.  TE or TM waves are launched into the tube or pipe by insertion of a probe into the end of a tube or through the wall of a pipeline, respectively.  In the case of pipelines, this antenna can be fixed or retractable and can be left in place for continuous monitoring if desired.

The pipeline can remain in service if a containment fitting is used to insert the antenna and maintain the pressure boundary.  For heat exchanger tubes, only one open end of the tube is interrogated.  In practice, the EMWs propagate past flanges and bends with little or no reflection of energy.  The detection range and resolution of the EMW-I™ test method will depend on several factors such as the attenuation characteristics of the product being transported, the diameter of tube or pipe under test, the tube or pipe material and surface conditions, but can range from ~100 feet for small diameter heat exchanger tubes to several hundreds of feet for large diameter natural gas pipelines.

WaveTrue is now working with an industry partner in Houston to validate the EMW-I™ test method on location and classification of anomalies such as simulated corrosion defects resulting in wall loss, longitudinal and circumferential crack defects, locating and quantifying anomalies such as hydrocarbon and water buildup, determining attenuation characteristics and determination of the range and resolution for test method on a test loop comprised of eight inch diameter carbon steel pipe.  The results of this validation testing will be more completely described and presented in this Forum Paper.


[7] Data quality of robotic pipeline inspection methods in addressing pipeline threats

Rod Lee, Pipetel, Toronto, ON, Canada
Paul Monsour, Southern California Gas Co., Los Angeles, CA, USA

Robotic pipeline inspection method has been more widely used for integrity assessment of natural gas and liquid product pipelines over the past 5 years.  While the operational advantages offered by this method may be more well-known and documented, there is relatively little literature on the quality of data and results acquired by a pipeline inspection robot and the specific threats that can be found.

The purpose of this paper is to examine the suitability of robotic pipeline inspection methods in addressing specific pipeline threats, including surface corrosion, internal and material anomalies, deformations, construction features, cracks and crack-like-features, and other useful pipeline features and characteristics including material verification.  The authors will provide results and specific examples with evidence of various pipeline threats and features, found by robotic pipeline inspection, that were subsequently excavated and validated.

This paper will also compare the quality of data acquired by conventional free-swimming inline inspection tools and robotic inline inspection tools.   We will also examine the limitations of robotic inline inspection method in addressing specific pipeline threats and the opportunities that exist in addressing them.

[8] Trenchless robotic cased pipe inspection via vents

John Abrashkin, Honeybee Robotics, Brooklyn, NY, USA

Honeybee Robotics and NYSEARCH are developing a robotic system for trenchless inspection of cased natural gas distribution pipelines. The Pipe Inspection Robot presents a new tool for pipeline operators to monitor assets, and to comply with DOT/OPS/PHMSA Pipeline Integrity rules requiring integrity assessment of pipes in high consequence areas. Using this system, operators can visually assess the condition of the casing and carrier pipe in real-time, without service disruption or costly excavation.

The Pipe Inspection Robot system comprises an inspection robot; power and communications tether; and operator control unit. Integrating patent-pending technologies, the Pipe Inspection Robot is the only trenchless tool available to operators who need to visually inspect cased pipe for cracks, corrosion, flooding, or other anomalies. Real-time images of the pipe can be used for pre-excavation inspection, or as an alternative to excavation.

A series of field tests with both East and West Coast NYSEARCH members in 2014 demonstrated the effectiveness of the Pipe Inspection Robot to navigate a variety of 2" vent pipes and visualize the annular space inside the distribution pipe casing.

[9] Robotic crawler ILI of an unpiggable 10” natural gas pipeline

Dr. Aaron Huber, Diakont, San Diego, CA, USA

Diakont Advanced Technologies was commissioned to assess the integrity of a natural gas pipeline that was partially buried under an urban area on a major North American pipeline. The company used a reduced size robotic crawler to successfully navigate a 10 in. pipe. The size of this pipe has previously been a limitation, making it ‘unpiggable’ using other ILI methods.

Designated as a high consequence area (HCA) due to being located in a densely populated area, this section of pipeline had never been inspected. Low flow, its narrow 10 in. internal diameter (ID), and its characteristics (tight bends, plug valves, etc.) made the pipe unsuitable for traditional smart pigging. However, the United States’ federal Pipeline and Hazardous Materials Safety Administration (PHMSA) regulations require specific integrity management programs in HCAs.

The pipeline’s inspection challenges could have forced its operator to replace an entire quarter of a mile length of pipe if they could not inspect the line effectively and on schedule. The technology gap between the inspection requirements and the available tooling forced the industry work with pipeline service vendors to develop a suitable solution.

New technology: reduced size and self-propelled
The new robotic crawler tooling traverses challenging pipeline geometries using a ruggedized multiple track system, which allows for navigation across horizontal surfaces. Moreover, the tool can extend the tracks to the pipe wall for stabilization. This arrangement provides the traction that is necessary to hold the tool rigidly in place while inspecting difficult-to access pipeline applications (such as inclines and vertical sections), where conventional ILI tools may not be feasible. This Sprinter system moves at a deliberate pace to provide accurate mapping of anomaly locations within the pipeline. Being self-propelled and bidirectional, the Sprinter can also be deployed and retrieved from a single access point, which was another key feature in its selection for this inspection program.

This presentation will provide details on the NDT tooling along with a case study for inspecting the unpiggable natural gas pipeline.

[10] In-line MFL inspection of a subsea vent line with a self-propelled robotic unit

Benny Hendra Syamsuddin, ROSEN Group, Kuala Lumpur, Malaysia
Corey Richards, ROSEN Group, Lingen, Germany
Daniel Schaller, ROSEN Group, Stans, Switzerland
Frank Mueller, ROSEN Group, Dubai

Offshore subsea vent lines were never designed to be internally inspected. They are therefore categorized as unpiggable pipelines. Operators, however, consider these subsea vent lines equally important and are keen to understand the overall integrity of their vent line system. Suitable in-line inspection solutions are therefore required and sought after.

Vent lines are a crucial part of processing systems and are utilized to ensure safe disposal of the excessive hydrocarbon gas inventory in the installation during operation, emergency, or shut down situations. Since the gas cannot be stored or commercially utilized, it is essential that the risk of fire and explosion be reduced by venting the excessive gas far away from a platform.

Challenges to perform in-line inspection for subsea vent lines are:

  • Conventional access for ILI tools not available
  • Pipeline can only be accessed from the main platform
  • No or very low flow and pressure
  • No previous inspection knowledge
  • Cleanliness is unknown

A sophisticated 10 &12” crawler unit capable of safely traversing non-operational vent lines, including the riser up to a distance of 2km, was developed. The self-propelled robotic propulsion unit utilized for the inspection combines various elements, including high resolution bi-directional MFL technology.  The specialized cam design driving components provide an increase in pull force capabilities, allowing the utilization of extensively tested high resolution MFL technologies. Further, this design allows for both vertical and horizontal bi-directional movement capabilities, critical for this application. This provides the operator with a full integrity assessment for the asset without reduction in data quality or the need to validate new measurement technologies.

This paper outlines the various safety mechanisms that are often overlooked when utilizing self-propelled inspection technologies. These mechanisms, both procedural and mechanical, allow for the inspection tool to traverse various obstacles, such as small deformations and debris, while also offering various failsafe options for tool retrieval in the event of a malfunction or when encountering an unpassable obstacle.

Recently, this system successfully completed multiple subsea vent line inspections in Sarawak Basin, East Malaysia. The tailored solution was selected because of the capabilities to provide high pulling force, able to cope with uncertain conditions of such vent lines, and high-resolution results. This paper discusses in detail the tool design, performance specification, extensive tests performed at ROSEN Technology and Research Center facilities, as well as the specific project aspects of the subsea vent line inspections.  The solutions outlined in the paper will not only highlight the capabilities to inspect complicated offshore assets, but further discuss how these solutions can be applied to other complex assets in need of inspection solutions.




[11] Managing inspection and assessment of unpiggable facitilites segments

Kevin Ostergren, Phillips 66, Houston, TX, USA

[12] Pigging four-phase crude pipelines for flow assurance, corrosion control, and inspection: challenges and solutions

Everett F. Johnson, Sr. and Randy Heath, Marathon Oil Eagle Ford Asset Team, Kennedy, TX, USA

Pipeline systems and production piping in unconventional oil & gas fields are extremely difficult to pig due to configuration, flows, and process conditions. Nevertheless, these pipelines require routine pigging for flow assurance, corrosion control, and inspection. Multi-phase flows in oil & gas pipelines include gas, oil, water, and paraffin/solids. This paper will discuss the challenges to pigging unconventional oil & gas pipelines presented by multiple connections and piping configurations, unknown configurations, and process conditions such as multi-phase flows, variable flows, and liquid slugging. One operator’s unique solutions and project experiences will be shared, for both maintenance pigging and smart pig inspections.

[13] Inspection of unpiggable large-diameter pipelines utilizing tri-axial MFL sensor technology

Paris Brad, Troy Hempel and Dale Simpson, Baker Hughes, Calgary, AB, Canada
Aaron Schartner and John Tang, TransCanada Pipelines, Calgary, AB, Canada

Inline inspection tools are one of the primary methods for inspecting and monitoring the condition of pipelines against integrity threats by pipeline operators for over 40 years. Technology has been in place to allow smaller diameter pipelines to be inspected without the use of permanent launcher or receiver facilities through the use of tethered inspection tools. For some pipeline segments with diameters greater than NPS 30 in size, technical and economic conditions exist that do not make the installation of permanent launch facilities feasible or prohibitive. In addition, service companies have limited their offerings to smaller diameter tethered inspections with the majority having been performed between NPS 2 and NPS 20 sizes, where the pipeline outage requirements, tool pulling limitations, costs, and other constraints have restricted the need for development to larger diameter pipelines.
Traditionally, the pipeline segments with diameters greater than NPS 30 without launcher / receiver facilities could not be assessed by Inline inspection and would be assessed by hydrostatic testing and/or direct assessments. Inline inspection for many pipeline segments is the preferred method of assessment as it provides feature specific information for the entire pipeline segment. The feature specific information allows operators to more accurately manage the potential threats on the inspected pipeline segment with detailed high resolution tri-axial MFL data. TransCanada approached Baker Hughes for a solution to inspect large inch pipelines (30” to 48”) utilizing their Tri-Axial MFL technology that do not have launcher or receiver facilities.

This paper describes a new approach that resulted in the successful tethered inspection of several pipelines up to NPS 42 in size with current high resolution tri-axial MFL inspection technology. Furthermore, the technical, logistical and project management challenges inherent in the project from both the operator and service company perspectives are explored including the mitigation of HSE risks and the engineering control measures implemented.


[14] INCOTEST tool for ROV deepwater inspection of unpiggable subsea pipelines

Roger Warnock, Delta Subsea, Houston, TX, USA

The INCOTEST (INsulatedCOmponentTESTing) Tool is based on the pulsed eddy current principle and is a reliable way to survey ferrous pipes and vessels through their thermal insulation and protective coatings.

The first prototype system to take the INCOTEST tool subsea can be remotely operated by ROV and maneuvered by the ROV manipulator. The system consists of 12 INCOTEST probes mounted on a frame with flaps hydraulically operated.

The benefits of Pulsed Eddy Current Testing and INCOTEST are:

  • Detection of surface and subsurface corrosion
  • Measurements of average remaining wall thickness within the interrogated area (footprint)
  • No contact needed for the measurement
  • No special surface preparation needed
  • Measurement through marine growth, fouling and concrete
  • Measurements performed in-line and done in depths down to 3000 meters (9842 feet)
  • Component evaluation at variable depths achievable through measurement at a range of frequencies or through different coil sizing
  • No consumable chemicals required
  • Fast: up to 1,000 measurements a day
  • Operates on batteries or mains ROV power

The more traditional inspection techniques are visual inspection and ultrasonic testing. There are several advantages of INCOTEST when compared to Ultrasonic Testing:

No need for grinding /surface cleaning
High production rate
Average wall thickness on footprint area
Measurement of the full material volume thickness through lamination
Geometric influence
Material magnetic permeability variation influence

Clean, smooth surface
Low production rate
Wall thickness local value
No geometric influence
Measures until lamination interface, no information about total remaining wall thickness
Material sound speed variation limited

[15] MFL miniaturization: Tool development for 2”pipelines with harsh environmental conditions

Basil Hostage and Daniel Schaper, 3P Services, Lingen, Germany

The paper describes the ambitious project to develop a 2“ inspection fleet (profile, geometry tool, MFL) for the inspection of a 2“ coiled tubing pipeline located in the north slope of Alaska. The 34.6 miles long pipeline provides arctic heating fuel from the Kuparuk oil field to a camp facility and was never inspected before. The pipeline in-between can be reached only by helicopter or by snow mobile in the winter. The main challenges for the project was on the one hand the design of the MFL measurement module due to the limited size especially in order to establish an appropriate magnetization level in the pipe wall. On the other hand to develop a complete system working in an environment temperature down to -5 degree ºF or less. The tools were developed and successfully verified in a test loop in Germany. All tool components like cups, electronics or sensors were specially checked to resist the required temperature requirements. The inspection is planned for the upcoming year.

[16] Developments in remote magnetic monitoring of carbon steel pipelines to locate and measure abnormal stress

Michael Staite, Speir Hunter North America, Nisku, AB, Canada

This presentation outlines recent developments in a novel remote sensing technique developed to detect localized abnormal pipe wall stress by mapping variations in the earth’s magnetic field around pipelines. Corrosion, metallurgical defects and ground movements result in areas of increased localized stress in pressurized pipelines and a direct relationship has been described mathematically relating magnetic field characteristics to the magnitude of stress due to magnetostriction.

The method is non-invasive and reports localized stress as a percentage of material specified minimum yield strength, its geometric center, accurate positioning of girth welds and 3 dimensional mapping of the pipeline route including depth of cover all to cm accuracy.

The presentation first explores magnetostriction in ferromagnetic materials and then how measurements of remote magnetic field can be applied to define the location of defects in operational pipelines, quantify the associated abnormal stress, report the position of girth welds and to concurrently report a 3-dimensional map of the pipeline route. The benefits of using this technique and a series of case studies are described to illustrate its use in practice in the field.

[17] Assessment of non-destructive evaluation tools for difficult-to-inspect pipes in liquid applications

Hans Deeb, PRCI, Houston, TX, USA

As non-destructive evaluation (NDE) tools and technologies continue to mature, new applications for difficult-to-inspect areas in liquid pipelines are becoming feasible and comparable in performance to existing technologies. However due to the novelty of these NDE tools, their performance track record is still lacking for the full adaptation in the pipeline industry. Technical research is needed to evaluate and quantify these inspection tools, expand their application' and increase the user confidence for integrity management of liquid pipeline systems.

PRCI has recently construed a 6-in diameter liquid test loop at its Technology Development Center (TDC) in Houston, TX. Many components of this loop are leveraged for the execution of this project, while a selected number of components are modified to simulate difficult to inspect pipe configurations. The primary objective of this study is to conduct quantitative and qualitative performance evaluation of smart pigging tools for liquid pipelines in difficult-to-inspect areas. The ILI tools detection and sizing capabilities is critical for an accurate defect assessment and establishing the pipelines future integrity and inspection regime.

[18] Paper to be announced

 Organized by:

Clarion Technical Conferences     Tiratsoo Technical

 Platinum Sponsor

A. Hak   

 Gold Sponsors

A. Hak    Rosen

 Silver Sponsor

Pipetel Technologies   

 Supported by:

Pipelines International     PIPE     Journal of Pipeline Engineering              PRCI     PPSA